At {{ChemicalBondsToCarbon}} we find that, apparently, the only elements seen in macroscopic quantities where a compound bonding it to carbon is unknown are radon and actinium.

I suppose for radon this is expected; it's not only radioactive, but it's also a noble gas. But actinium's longest-lived isotope has a pretty respectable half-life of about 22 years, the second-longest-lived one has been tested as a radiopharmaceutical, and its lighter congener lanthanum has a respectable organometallic chemistry. So, is it really the case that no compound with a C–Ac bond is known, or is the template just outdated? Double sharp (talk) 12:42, 27 September 2025 (UTC)[reply]

I feel like there is no Ac-C, the closest thing I can find is an endohedral fullerene. Radiopharmaceutical ²²⁵Ac complexes use Ac-N and Ac-O instead because Ac-C are water-sensitive like La-C, so they are too unstable to use in body.

I also doubt the existence of Ra-C because I can't find information of the claimed acetylide, but that doesn't sound right when Bk-C is known, perhaps people are avoiding ²²⁶Ra and ²²⁷Ac (produced from ²²⁶Ra) at all costs due to ²²²Rn emission from decay. Nucleus hydro elemon (talk) 14:33, 27 September 2025 (UTC)[reply]

How can I visualize GTDB tree files? They do not work on any software, I don't know how Wikipedia editors got these trees visualized. Jako96 (talk) 13:39, 28 September 2025 (UTC)[reply]

The link in the infobox of that article to https://gtdb.ecogenomic.org/tree seems to allow visualisation. Do you need more than that? Mike Turnbull (talk) 15:03, 28 September 2025 (UTC)[reply]

See Asgard archaea#Phylogeny. Yes, I do need more than that, that "tree" is just their taxonomy. I need to see their phylogenetic analysis results, not just their taxonomy. The "ar53_r226.sp_label" file does not work on any program. This is my problem. Jako96 (talk) 16:47, 28 September 2025 (UTC)[reply]

Same with their bacterial phylogeny (that file is for archaea). Jako96 (talk) 16:48, 28 September 2025 (UTC)[reply]

Upon seeing the news of Jane Goodall's death, I read her article and observed that she experienced prosopagnosia, a difficulty or inability to recognise faces. Not surprisingly, our article talks exclusively about its effects on recognising human faces. Would it affect one's ability to recognise the faces of individual chimpanzees? Nyttend (talk) 21:03, 1 October 2025 (UTC)[reply]

From an interview whose text I found only in the html source of this page:

Did your prosopagnosia — “face blindness” — make it more difficult to recognize individual chimps at first?

Jane Goodall: Yes, it did. It did take me longer to know the chimps too. But I haven’t got the most extreme form. Once I know somebody, I know them. But chimps are no easier than people.

 ​‑‑Lambiam 10:55, 2 October 2025 (UTC)[reply]

Lambiam has certainly provided you with the definitive response to your question, but I'll add a little bit of extra detail about the mechanics involved--though in the broad-strokes you will probably find some of it very obvious. Dr. Goodall herself provides some pretty valuable insight into the matter, impressionistic though it might be, because the number of people who have trained themselves to distinguish between non-human ape faces with anywhere near the efficacy with which they recognize human faces, be they primatologists or not, is not exactly massive, and even accounting for the fact that there is some degree of partial congenital prosopagnosia in the general population (in addition to the generally more severe variety that results from trauma or emergent gross defect), the overlap between the two populations can only contain so many individuals--let alone individuals famous enough for the perception in this respect to have become a matter of record. Now that we've lost this unique mind--not just in regard to above overlap, but in so, so many ways... :( -- I can only wish i had been able to ask her follow up questions, as someone with some more formal background in visual cognition and a more amateur experience with ethology.

Of particular relevance to your inquiry, its important to note that perception of the face is a fairly distributed process, taking place in a number of regions mainly in the occipital lobe (which centers are largely concerned with processing precise geometries and other information taken from the fovea especially catches as your eye jumps from feature to feature during the visual process--you might say its visual centers tend to be the locations of "early"* processing) and the temporal lobe (which centers tend to be involved in coordinating and further processing visual information to create the ultimate qualia, by combining individual features into a ghestalt whole, which in reality you are never actually "seeing", in the literal physical sense of where the eye is focused, all at once, but which the temporal creates partly by combining information from lower in the processing chain and applying a whole bunch of assumptions--some conditioned, but largely nativistic--about how faces operate). And then you also have to take into account that the face is not a static object, but rather a highly malleable one whose behaviours are another significant pre-occupation of your brains, and that two is a function of "facial recognition" and one which pulls in yet more neuroanatomical regions. I'd have relished the opportunity to ask Dr. Goodall 1 or 500 questions about her perceptions on chimp emotional expression...I'm sure there's a non-trivial amount documented, but....what a lose for us all, this one is...

*meaning not necessarily first in time (since facial processing operates by many parallel processes simmultaneously with some degree of back-signal between that work in tandem during the process of creating a percept) but rather "earlier" in the sense of being more likely to send signals out to further processing (typically but not always in discrete regions of the temporal lobe). SnowRise ^{let's rap} 04:11, 3 October 2025 (UTC)[reply]

For matter and antimatter to destroy each other and create gamma rays, does the antimatter particle need to be the antiparticle of the matter particle?...For example could an antineutron and a proton destroy each other? And could the rays created ever be less energetic than gammhrays, like radio waves?Rich (talk) 20:05, 4 October 2025 (UTC)[reply]

A full answer will probably involve the notoriously difficult field of quantum chromodynamics, but a proton is two up quarks and a down quark, whereas an antineutron is an up antiquark and two down antiquarks, so just combining those naively it would seem that you would get an annihilation between an up and an anti-up, and between a down and an anti-down, and be left with a combinaion of an up and an anti-down, which seems to be a positive pion. No, I don't see how you're ever going to get radio waves (except maybe after a huge redshift); these interactions are far too energetic. --Trovatore (talk) 20:31, 4 October 2025 (UTC)[reply]

Thanks. Could a positron annihilate with a proton? On the other hand, could an electron actually be antimatter and we don't realize it? Also if an uncharged particle meets its uncharged antimatter antiparticle, will they annihilate each other even though uncharged?Rich (talk) 21:48, 4 October 2025 (UTC)[reply]

An electron cannot be antimatter because it has an antimatter counterpart, the positron. {The poster formerly known as 87.81.230.195} 90.193.153.108 (talk) 22:49, 4 October 2025 (UTC)[reply]

Things like electric charge and lepton number must be conserved (in the Standard Model at least; there's some theoretical physics beyond the Standard Model, but it's all pretty speculative), so proton + antineutron must at least give something with a positive charge, like a positron and if so, to conserve lepton number, also a neutrino. Positron + proton has baryon number +1, lepton number -1 and charge +2 and this must also be the case for the products. In general, a particle needs its own antiparticle to annihilate, but it may be able to interact with others.

If we declared all positive leptons to be matter and all negative leptons antimatter, and flipped the neutrinos likewise, physics wouldn't change (B - L would become B + L, which would actually be good for symmetry). We only call positrons antimatter because they're in our universe rarer than electrons.

An uncharged particle and its antiparticle can still annihilate, but as they don't couple to the electromagnetic force, they don't make photons, but something else. Neutrons and antineutrons are composed particles, consisting of charged (anti-)quarks. They can create a big mess of particles when annihilating, including photons. PiusImpavidus (talk) 09:17, 5 October 2025 (UTC)[reply]

(The pion, of course, won't last long, a nanosecond or so. I'm fairly sure that, whatever the way-beyond-my-expertise details are along the way, your end-products are going to be some photons, some neutrinos and antineutrinos, and a positron.) --Trovatore (talk) 21:45, 4 October 2025 (UTC)[reply]

But when a neutrino and an antineutrono annihilate each other,(if they do annihilate each other), wouldn't the energy released be so very small that the radiation released needs to be less energetic than a gamma ray?Rich (talk) 21:53, 4 October 2025 (UTC)[reply]

This 'annihilation' (which would be a very rare event) wouldn't release electromagnetic energy, it would (it is thought) create a Z-boson, which would then decay to form another matter-antimatter pair, usually another neutrino and antineutrino (see W and Z bosons#Decay). {The poster formerly known as 87.81.230.195} 90.193.153.108 (talk) 22:42, 4 October 2025 (UTC)[reply]

Antineutron can in fact annihilate with proton producing several pions. In fact once pions were thought to be bound states nucleon-antinucleon. Ruslik_Zero 20:34, 5 October 2025 (UTC)[reply]